Despite the changes in warfare, Russian forces retain the ascendancy and are making slow but steady advances in the east and north of Ukraine. Russia has also caught up in UAV technology after falling behind early in the war, according to military analysts, and like its enemy is churning out drones domestically at a rate of millions a year.

Russia's Defense Ministry said its forces shot down at least 143 Ukrainian drones on Wednesday night through to Thursday afternoon, with at least three craft intercepted over the capital Moscow region.

Moscow barreled hundreds of drones toward four key regions in Ukraine overnight, just as lawmakers in Kyiv scrambled to approve additional defense spending against the backdrop of intensified Russian attacks over the past few days.